Month: October 2009

Cloud Computing eliminates restrictions due to the number of servers in the QA lab, and thus allows concurrent testing by developers and QA engineers. By making it easy to test often, and to expose early releases to the outside world, Cloud Computing will improve product quality

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Does this story rings familiar? You are in a planning meeting for the next release, and learn that in addition to supporting Oracle 11g, the product will also need to support Microsoft SQL Server 2008 (or DB2, or mySQL, or PostgreSQL). Once the typical brouhaha dies down about how complicated this will be, how the whole code will need to be ripped apart, and how much time this will take, the Director of QA turns to you and asks for a couple of additional servers for the QA lab, so that the software can be tested on the two databases in parallel; minimum of three servers: 1 for the database, 1 for our software, and 1 for the test fixtures. The following day, it’s the developer lead’s turn to ask for more servers: need at least 1 “populated” database against which the developers can test, plus another set up for the daily build, etc. Makes perfect sense … Except that no budget has been allocated for these servers! Soon you find yourself with your beggar’s cup in the CEO’s office, explaining to him, and the CFO, why your team needs these extra servers when “you already have so many!!”

Rejoice! Here comes Cloud Computing to the rescue ..

Cloud Computing could not only eliminate the need to purchase servers for testing, but also actually radically improves your ability to test, and thus improve product quality.

Cloud Computing, such as Amazon EC2, offers the ability to deploy (and un-deploy) software on demand. One pays “by the hour” of computing used, and storage and bandwidth consumed. This is perfect for testing (by developers and by QA): compute load varies greatly over the cycle of the day, as well as the cycles of the release.

First of all, every developer can now have his/her own test setup against which to test. There is no limitation of hardware, no begging, borrowing or stealing from your colleagues for unutilized servers. One can just deploy at will. Furthermore, there is no restriction on the number of servers. So if you need to test a four-server cluster, you don’t have to hunt around for free servers, you just do it.

Similarly the daily build can deploy to multiple test environments concurrently and thus accelerate the validation of the build.

Finally, the QA team can also test in multiple environments simultaneously, e.g. Oracle and SQL Server at the same time! This offers the potential benefit of being able to test a much larger number of deployment scenarios, than would be possible using one’s own hardware.

First and foremost, all the tests must be automated. While technology has created virtual servers, it has not yet inventing virtual test engineers J. Secondly, one will have to build tools to automatically deploy, e.g. from the build environment, the new version of the software, and the test fixtures, as well as collect the results of the test runs.

One can be quite creative with the test management tools. For example, if a test setup encounters a high-severity bug, you could configure your test software to pause the test, deploy to a second environment and continue testing in the second environment. This allows you to go back to the first test setup to troubleshoot, and find the cause of the crash.

Another fascinating advantage is that you can deploy demo or beta systems at will (assuming your deployment model allows it.), and let your sales team or prospective customers to “play with” the early release. By making it easier to expose early releases of the product to the outside world, Cloud Computing further improves the quality of your product.

Will you save money by testing in a Cloud Computing infrastructure?

Obviously the answer depends … on your usage, but also on factors like how much data you need to keep permanently in the cloud. For example you may need to permanently store a synthetic database of a million users (it would be too slow to upload it each time). You will also incur higher networking traffic.

In addition, you may not want to move all your tests to the cloud. For example, you may want to keep your stress-tests, or longevity tests in-house, since these will be running 24×7, and you may want the option of running them on bare-metal.

At the end of the day, to me the attraction of Cloud Computing for testing is that it will increase quality (in addition to reducing costs). It will allow each developer to have access to a test environment at will. It will create an additional impetus for test automation. Cloud Computing will also allow the concurrent deployment of tests to an arbitrary number of computing environments, and make it easier to give early access to your customers. Net-net, this translates to more tests in the same amount of time with less effort. It’s all goodness.

Design reviews do not simply allow me to have my design reviewed, but also give me the opportunity to inspire my team mates with my own ideas, and kickstart brainstorming discussions – thus fostering team creativity

By pure coincidence, I recently listened to a 2008 interview of Ed Catmull, cofounder of Pixar and President of Pixar and Disney Animation on the topic of “Pixar and Collective Creativity”, by Harvard Business School IdeaCast.

The interview centered on mechanisms to foster innovation – for which Pixar is so famous. Ed Catmull’s emphasizes the importance of communication at and across all levels, and he constantly encourages anyone and everyone to share their thoughts, critique, and suggestions.

To this effect, he encourages all the teams at Pixar to have dailies: meetings at the end of the day where each of the animators shows to the rest of the team their accomplishments of the day, whether complete or not. This is a vulnerable moment where one has to show work in progress, warts and all, to colleagues (there’s always a bit a competitive spirit at work) and possibly Ed himself, if he happens to drop by. Yet, it is also a great opportunity to not only stimulate suggestions from one’s colleagues on how to improve one’s own work, but also to give ideas, or kick-start a brainstorm about the project in general, and other people’s work.

To me, the concept of dailies translates naturally to design reviews in the software development world, as I blogged a few days ago. I don’t necessarily advocate for daily design reviews, but certainly for frequent ones; most importantly early on, before foundational decisions are made, so as to actually benefit from the team’s suggestions.

Ed Catmull highlights another set of benefits of design reviews that are potentially even more powerful to foster team creativity (rather than just individual creativity) than simply having my design double-checked: my own work and ideas can inspire my colleagues, and the very process of reviewing my work can also stimulate brainstorming discussions about new concepts and ideas. This is powerful stuff!

To me the same argument can be made about the importance of design reviews as is made for pair programming – and conversely I have a hard time understanding why one would advocate pair programming and not design reviews: “two heads think better than one”.

Any “bug” that can be found during the design phase, will cost a lot less to fix, than if it is found during the implementation phase.

Furthermore, the advice of my peers is most useful to me in the early stages than when I am 95% done. It’s a lot easier to incorporate their suggestions, or explore alternatives, when no code has been written.

In summary, in my view, the best approach is to spend time upfront figuring out the design, and once I have a good idea of what I want to build, to code it using the Agile methodology. In other words: “Think holistically; code-and-test incrementally”

So when should a design review be held?

As a developer, I want to hold a design review when:

I need help

I want to confirm that I am on the right track

I want to double check that I have not missed anything

I want to communicate some assumptions that I have made that impact other components.

The design review is important not only to validate the design, but also to communicate: what I plan to do, and how it will impact others: developers, as well as testers, and even tech support, documentation, and product marketing

In the next post, I’ll publish a Checklist. Its purpose is primarily as a tool during the design process itself, to make sure that all aspects of the design have been considered. It is also useful during the design review session as a guide for the discussion. Finally, you can infer from the checklist all the people that need be informed about this design, and ultimately the implementation